Hydrodynamic balance.



Eff'. FISHER. HYDRODYNAMIG BALANCE.V

APPLIcAxIoH FILED 11111.?, 1911.

20 I w i' v WITNESSES INVENTOR i Patented Jan.7,1913.

ERNEST r. rrsnnmor rrrTsBUBGn, PENNSYLVANIA.

HYDBODYNAMIC BALANCE.

, Specicaton'of Letters Patent.

Application mea Karen-7, 1911. serialnaelass?. H E g D To all ev/10m, it may concern:

tfjknown thatv I, ERNESTF. FISHER, a `ident of Pittsburgh, in thelcounty of Allegheny and State of Pennsylvania, have 5 invented certain new 'and useful Improveilments in Hydrodynamic Balances, of which "the, following is a specification.

The object-of this invention is to provide a highly efficient instrument of simple and improved yconstruction for recording vaiiations of fluid pressure, andparticw. "lanly the difference between two pressures which may be in opposition to each other, or otherwise, according `to the circumstances underf which they exist, or the conditions ying the invention in the aspect last mentioned it is in effect a differential pressure gage. ,i Broadly considered, the invention consists-of a movably mounted. frame. provided Q .withmeans for maintainingi-t.normally'in a given position, and wlth means for communicating the pressure or pressures to be gaged to the frame in snchmanner as to move itk from normal4 position andthereby effecting the movement of suitable'reeording means. Specifically, the invention consists of a balanced frame which carries .a4 magnet whichcauses the recording` means to move In the preferred adaptation disclosed herein the'balanced magnetcarrying fra-ine is'inclosed in a liquid filled chamber, andlffthevpressure or pressures to be gaged arecommunicated to one or a pair of hollow kheiibodies" carried by `the frame.l the bodies oper in conjunction` with air lconfined luch like scale pans in determining L :illations of the frame, the pressure .orpressures to be gaged being communicatedto' neor bothiof the bodies in man- -ner presently to be explained.

` Infthefaccompanyin'g drawings, Figure 1 is ar-'vertical longitudinal 'section of apparatusll 'embodyingthe invention, taken on line 1 -`-1 ofFig. 2, and Fig. 2 is a cross- `seeti'o`I'-`1`-'oii'fline 2 2 of Fig. 1. Fig. 3 is a magnet-operated re 10, and with the hollow bodies4 14 'and 15 detail? of 'the pivoted corderor marker;

Referring to the drawings, 2 designates a closedchamberwhich may be formed in sections as at 3,'the chamber being filled with liquid 4, as .water 4orafsluitable oil. At the lowergportion of chmlier preferably re the two adjacent fthe bottom under which theinstrument is used. View- `the bodies without touchin 17 fai-fd 18 are 'curved comp ementary with the arc of ymovement ofthewbodies as'they supplemental chambers 5 and 6to-which lead the pressure communicating passages or ports T and 8, respectively, said ports being here shown cored in the walls of chambcrv2 and lrising to the full height of the liquid 4 within said chamber. The passages 'I and 8 are filled with liquid vas shown, and this liquid partially fills chambers 5 and 6.

`'ithin chamber 2 is the movable frame 9 here shown centered by the knife-edge fnlcrum 10 on hangers 11, the equilibrium of the frame being normally maintained by the depending weight 12. In line with this counterweight and with fulcrum 10 is the compound magnet 13 which projects up# Patented Jan. 7,1913.

Jwardly into close proximity to the recessed top wall 2 of chamber 2.

Carried by frame 9 at Vopposite sidestof its fulcrum are the hollow bodies 14 and 15, each provided with an openingl at its bot- .extending from the upper portions of cham-v bers 5 and 6 and throughsaid openings into them. .Pipes Gscillate with frame 9, sdthat such movement' is not impeded in an way v On top `of chamber 2 is t ,receptacle 19 which contains a suitable fluid 20vfor supporting metallic float 21 in relatively close proximity to the extremity of magnet 11,v

the latter operating' through' wall 2 and Huid 20, and moving the float `tolone side or the other according to the -direction in which the magnet oscillates. Pivoted at 22 u on the float is elongated arm 22 .whicheX-f tends through the slotted ends of receptacle 19 with one end of the arm carrying a suitable marker or stylus 23 of usual construction, the marker being held by the arm each lcontaining the 'sameI amount of liquid '1 admitted through openings 16, the fluid in passages 7 .and 8 which extendsto an elevation eq'ualto that of the main fluid body 4 preventing,they lhollow bodies, under normal conditionsefrom `fillingl further, as wil-l'be understood. Pipes are connected to the upper ends 7, 8 of passages 7 and 8 for communicating the pressures to be gaged. When operating as a differential 'gage' the parts maintain the central posltlon 1nd1- cated in the drawings when the pressures' that body 15 lowers proportionately and body 14 rises, thus oscillating frame 9 and moving magnet 13 toward the right hand, Fig. 1, with the magnet recording arm moving therewith, as will be understood. A reverse action ensues if the preponderating pressure is communicated to port .8. It is -obvious that by closing pressure communication to one or the other of ports 7 or 8, the apparatus will operate for gaging or recording a single pressure communicated to the instrument through the remaining open port.

1. The combination of a closed chamber filled with liquid, a frame mounted to oscillate on a horizontal axis within the chamber, a hollow body within the chamber and movable with said frame, said body being open for the admission of fluid from the chamber and partially filled by said liuid with the remainder of the body filled with air, a pressure communicating conduit in communication ...with the air space of said bodyand movable' recording mechanism actuated by said/frame.

2. Thefcombination of a closed chamber filled with liquid, a magnet mounted on a horizontal axis Within the chamber, a hollow body within the chamber and movable with the magnet, said body being open for the admission of fluid and normally partially filled with fluid with the remaining space therein filled with air, va supplemental air chamber, an air conducting connection between the latter and the air Iconfining portion of the hollow body, a pressure communieating conduit extending to the supplemental chamber, and recording means actuated by the magnet.

3. The combination Aof a closed chamber filled with liquid, a magnet mounted on a horizontal axis within thecliamber, a hollovs7 body within the chamber and movable with the magnet, said body being open for the admission of fluid and normally partially filled with fiuid with the remaining space therein filled with air, a supplemental air chamber, an air conducting connection between t-he latter and the air confiningportion 'of the hollow body, a pressure communicating conduit extending from the supplemental chamber and rising to the helght of the main chamber, said conduit and a portion of the supplemental chamber1 containing a liquid, and recording means actuated by the magnet.

4. The combination of a closed chamber filled with liquid, a magnet, a magnet-carrying frame within the chamber and balanced on a horizontal axis, a hollow body sup' ported by and movable with the frame and open vfor the admission of liquid from the chamber, the body being partially filled with such liquid with the remainder of its interior'filled with air, and a conduitfor communicating the pressure to be recorded to the air-filled portion of the hollow body, and recording' mechanism actuated by the magnet.

5. The combination of a closed chamber filled with liquid, a frame within the chamber and mounted on a. horizontal axis, a magnet carried by the frame, hollow bodies supported by the frame at opposite sides of its pivot and movable therewith, the bodies being open for the admission of fluid'from t-he chamber and partially filled with such fluid with the remainder of the space therein filled with air, pressure communicating conduits in communication respectively with the hollow bodies, and recording means actuated by the magnet.

6. The combination of a closed chamber filled with liquid, a frame within the chamber and mounted to oscillate on a horizontal axis, a weightl depending from the frame and a magnet projecting upwardly therefrom, hollow bodies at opposite sides of the frame axis and movable with the frame, the bodies having openings at their under sides for admission ofA Huid from the chamber with the bodies partially filled with such fluid and the remainder of the space therein filled with air, two supplemental air chambers with means establishing communication between said chambers respectively and the air confining portions of the hollow bodies, pressure communicating conduits extending to the supplemental chambers with fluid filling said conduits and partially filling 'the chambers, and recording mechanism actuated by the magnet. A

7. The combination of a closed chamber filled with liquid, a frame within the cham-- ber 'and balanced on a horizontal axis, a magnet carried by the frame, hollow bodies supported by the frame at opposite sides of its axis and movable with the frame, each of the bodies having an opening at its under side for admission of uid from the chamber and with the body partially filled with such A fiuidand the remaining port-ion of its space f filled withl air, supplemental air lchambers said conduits and partially filling the sup- 10 beneath said frame, Vpipes extending from plemental chambers, and recording mechathe supplemental 'chambers and curved comnism actuated by the magnet.

plementary with the arc of movement of the In testimony whereof I aiix my signature 5 -holloW bodies and extending ythroughthelootin presence of two witnesses.

tomopenings' of the' latter and into the 'air ERNEST F. FISHER. confiningr portions of their interior, pressure Witnesses: v communicating conduits extending to the J. M. NESBIT supplemental chambers with liquid filling ALEX` S. MABON.

Copies: of this patent may be obtained for iive cents each, by addressing the Commissioner of Patents.

Washington, D. C. t 

